Opaque projection system



y 2, 1929- J. T. REMEY ET AL 1. 19. 50

OPAQUE PROJECTION SYSTEM Filed Feb. 24, 1927 2 Sheets-Sheet l July 2, 1929. J. T. REMEY ET AL 1,719,450

OPAQUE PROJECTION SYSTEM Filed Feb. 24, 1927 2 Sheets-Sheet 2 ATTORN Patented July 2, 1929.

UNITED STATES PATENT OFFICE.

JOHN T. BEMEY AND THOMAS K. MELOY, OF NEW YORK, N. Y., ASSIGNORS TO TRANS- LUX DAYI-IGHT PICTURE SCREEN CORPORATION, OF NEW YORK, N. Y., A CORPO- RATION OF DELAWARE.

OPAQUE PROJECTION SYSTEM.

Application filed February 24, 1927. Serial No. 170,489.

This invention relates to. an opaque projection system for use in projecting upon a screen matter contained upon an opaque object. Opaque projection systems have been devised but they have not been generally successful because of the fact that a large percentage of the light used is wasted. The light must be projected upon the object and then reflected to the objective. In order to do this it is practically necessary to place the light at one side of the object, which means that a large portion of the light reflected from the object does not reach the objective and therefore is wasted.

It is the object of our invention to provide a system which will utilize a great deal of this light employed in illuminating the object to be projected, and which is wasted in existing systems. The manner in which we accomplish this object will be best under stood from the following description when taken in connection with the accompanying drawings, in which:

Figure 1 is a vertical sectional view through one embodiment which our invention may take this figure being taken on the line 1'1 of Figure 2.

Figure 2 is a view taken on the line 2-2 of Figure 1.

Figure 3 is a diagrammatic horizontal section through the center of the system.

Referring now to the drawings in detail, we have shown our invention as embodied in a projector having the front wall 1 and the rear wall 2. Supported on the front wall is an objective 3 of any suitable form and the rear wall is provided with an opening 4 in the axis 5 of the objective. A suitable support 6 is disposed behind the opening 4', this support being adapted to hold in the opening the object to be projected. It is to be understood that while we show and describe our invention as einbodied in one form, we do not intend to limit ourselves thereby as the principles involved may be embodied in a plurality of forms without de arting from our invention.

be support 6 is here shown as mounted upon a bracket 7 which is hinged at 8 to the back wall and is held in its upper position by means of the coil spring 9, where it supports the object 6'. Disposed upon opposite sides of the axis 5 are sources of llght, here shown as lamps 10 and 10. While we reflector 11.

have shown two lamps, it is to be understood that this number may be varied as found expedient. Enclosing the lamps and the opening 4 is a reflector 11 having an opening 12 on the axis 5 and registering with the objective. The reflector is shown as being secured to the rear wall by suitable fastening means 13. The reflector 11 and the inside surface 14 of the rear wall form a housing which encloses the object supported in the aperture 4 and the lamps which form the sources of illumination, and it will be seen that these elements are completely enclosed with the exception of the opening 12, which is essential to permit the light to pass through the objective 3. The interior surface of the housing, includin the surface 14, is preferabl one which is highly reflecting and di using, such as a dull white one.

lVhile we have shown the reflector 11 as hemi-spherical in shape nevertheless other forms may be employed if found suitable. The gist of the invention resides in the provision of a reflector enclosing the source or sources of light and the object to be projected, whereby substantially no light may escape from the enclosure except what is reflected from the illuminated object. It will be seen that a ray of light emanating from one of the lamps and striking any part of the reflector 11 will strike either the object in the aperture 4 or the surface 14 adjacent that aperture. The light striking the object in the aperture will illuminate it, some of this light being reflected into the objective 3 and some being reflected to the This latter light will again be reflected back to the object or to the surface 14 adjacent thereto, Any light striking the surface 14 will be reflected therefrom to the reflector 11 and ultimately the greater part of this light will reach the object to be projected. The result is that substantially all of the light emanating from the lamp will ultimately illuminate the object and will strike it at an angle of incidence such that it will be reflected from the object through the objective 3, thus greatly increasing the illumination on the screen to which the image of the object is projected. This result is best achieved if the interior surface of the reflector and the surface 14 are diffusing, so that light reflected therefrom is broken up into many small beams or rays of light.

The operation of our invention is illustrated in Figure 3 wherein a ray of light is shown in full lines as leaving the lamp 10 and striking the reflector 11 at 16. This ray of light will be deflected and strike the object in the aperture 1 at 17. The object will be illuminated by this light and certain parts of the ray will be reflected as along the dotted line 18, which will be deflected again at 19 and 20 and will strike the object again at 21. In other words, the light which is reflected, as along the line 18, instead of being wasted, is saved to a large extent and used to illuminate another part of the object. Other rays of light will, of course, originate at the point 17 and will either pass through the objective 3 or will be caught by other parts of the reflector and deflected back to the object. Similarly it may be shown that a ray of light emanating from the lamp 10 and striking the surface 14 adjacent the aperture 4 will be deflected back and caught by the reflector 11 which will deflect it again to the object in the aperture. The path of such a ray is shown by the dot-and-dash line 22, which is shown as leaving the lamp 10 and striking the surface 14 at 23 and then being reflected to strike the reflector 11 at the points 24, 25 and 26 and finally reaching the object in the aperture 4 at the point 27. By providing the diffusing surface on the interior of the housing, both on the reflector and on the enclosed part of the rear wall, it will be seen that the illumination of the object will be increased and made more uniform, because a ray of light striking the surface will be broken up into smaller rays which will more evenly illuminate the object.

We claim:

1. An opaque projection system comprising a casing having front and rear walls, means to dispose an object in said rear wall, an objective in said front wall, a source of light disposed between said walls, and a reflector enclosing said light and extending to the rear wall and having an opening therein registering with said objective, the inner surface of said rear wall between said object and said reflector being reflecting.

2. An opaque projection system comprising a casing having front and rear walls, means to dispose an object in said rear wall, an objective in said front wall, a source of light disposed between said walls, and a reflector enclosing said light and extending to the rear Wall and having an opening therein registering with said objective, the inner surface of said rear wall between said object and said reflector being reflecting, said reflector and said reflecting surface of said wall also diflusing'the light.

In testimony whereof, we have afiixed our signatures to this specification.

JOHN T. REMEY. THOMAS K. MELOY. 

